Printing with pressure

The video of [Thibault Brevet’s] printer makes it look like he’s actually designed a vinyl cutter (watch it after the break). But at the end of the printing process you see that the top layer was actually a piece of carbon copy paper and the magic was happening underneath. The print head applies enough pressure to transfer the blue-ish printing ink onto the paper giving the result seen above. He’s driving this with an Arduino and feeding data using Processing.

[Thibault] left this link in the comments from the LEGO printer post. Shame on him for not tipping us off as soon as he posted info on this hack. Don’t underestimate yourselves, if you hack it we want to hear about it!

I find that I prefer when people write up projects with an eye towards reproducing the work done, especially when the methods used are opaque… or if there is some “secret sauce” that is non-obvious to the average wanna-be hacker.

However, sometimes it’s good enough just to know that something can be done. In truth, while we look at this site regularly, most of us won’t bother trying to build everything we see showen on the site.

We’re happy just to file away the idea, perhaps thinking that maybe we’ll do something like that one of these days.

I want to thank the HAD guy for providing the “secret sauce” in the description – namely, that the guy is using carbon paper to produce the image. Never seen it done in this manner, even though I already knew carbon paper was often used to transfer layouts to metal for cutting and drilling. It’s a neat trick.

I have no problem with the HAD mix of old, new, interesting and “non” projects. A lot of interesting mechanical ideas have been rehashed for about 3000 years, and still get trotted out as new technology. That’s OK by me.

It’s the same with electronics, or flying cars, for example. As long as the focus of hackaday is guys* who do stuff, we’re golden.

@Heliostat: Carbon paper is fine, it is simply ink power bound to a paper backing with wax. Carbonless copy paper is the hazardous version, but that requires a special page to be copied onto and as such I don’t believe that is what this project is using(though I could be wrong).

Carbon paper is only toxic if burned. Also the key ingredient to carbon paper is carbon black, which is the same ingredient as laser toner. This actually seems less polluting than laser toner if the paper substrate for the carbon paper is made from recycled paper, which I would imagine that it is.

In exchange, here is a little known fact: In a few years, it will be common for “[insert name of anyone likely to have access to a taser]” to be issued flashlight-sized imaging devices that are basically portable X-ray machines operating at fairly high frequencies.

Cheap to build, fun to play with and best of all – since it’s made of technology – it won’t even be prohibited by the constitution.

This technology has been around for a while, just waiting for the patents to expire before they become common as dirt.

These allow the operator to see through walls, clothes, toilets, car bodies, locked desks, under beds, into closed rectums… indeed, they’re more or less portable versions of the expensive toys we sold for a fortune. Anyway, back to carbon paper…

It turns out carbon paper has some very interesting properties at certain frequencies, especially if you have a couple layers of it, or if you make multiple [plastic or paper]/[carbon paper] layers.

It’s also very interesting to read about stealth technology, which is often a high tech version of carbon paper. Real carbon paper is hard to find, and pseudo-carbon work-alikes based on tiny dye capsules don’t have interesting RF properties.

What?! How many prints do you get from a gram of carbon black in carbon paper form vs a gram in toner cartridge form? Admittely I don’t know, but I can’t see any conceivable way in which carbon paper could NOT be horrendously wasteful.

@Thibault, if you’re reading, I’m curious to know why carbon paper was the medium of choice…it’s certainly a very neat project, but seems a little impractical.

@Brian It wouldn’t be QUITE as simple as just swapping out the pressure head for a cutter. You would have to switch to sending out a vector-based code (pen down, move 5,2, pen up, move -2, 3…). It’s certainly possible (assuming the feed can operate in either direction), but not just a simple swap-it-out solution.

Your mechanism reminds me of the Portaterm RS-232 terminal I used as a kid. It was built into a briefcase, and featured a built in acoustic coupler modem (110 baud, of course.)

The reason the Portaterm is similar is that instead of a Selectric golf-style type ball, a small, flat hammer was located in front of the paper, with the ribbon sandwiched between the hammer and the paper. So there was this very simple moving mechanism up front, pounding away and magically producing letters, while all the real magic was hidden out of sight – the font cylinder rotated behind the paper, instead of the traditional flat platen.

yeah basically i didn’t submitted it here cause i didnt have time right now to properly document it ! I was on my way to do a documentation about parts list, building, electronics involved and source code but you published it before i could haha !

i will tell you again when i’ll publish everything so you can make an update but for now i’m looking first for my exams !

– XY moves are done via 2 stepper motors each one controled by a ULN2004A
– print head is a little solenoid triggered via a TIP102
– I got a processing sketch that reads a black and white bitmap picture, first stocks in an array the coordinates of each black pixels, then calculate the X offset and Y offset from coordinate 0 (origin,0,0) to the [1] coordinate from the array, and then just sends to the arduino the XY move to do, arduino moves the head accordingly, fires up the print head and tells back my sketch that it printed the point, then when the sketch receives confirmation of the pixel print, it calculate the next X and Y move from point [1] to [2] and again and again until the end.

There is no special point in using carbon copy paper, it was a school project for my graphic design course where we were forbid to use regular printing techniques so we had to develop a method of our own, so i simply built my own printer instead of just use like potato stamps haha :)